Mold for slide fasteners



Feb. 21, 1950 R. LOW

' MOLD FOR SLIDE FASTENERS '7 Sheets-Sheet 1 Filed March 3, 1945 HGZ INVENTOR. V icharoz Low ATTORNEYS Feb. 21, 1950 v ow 2,497,951

I MOLD FOR SLIDE FASTENERS V Filed March 3, 1945 7 Sheets-Sheet '2 4' Q I; III I I I I a l I L I In i II in} I III I I I I I I I I I I I I IL!) I c0 I I I I I I I '3 I I I LI- I X INVENTOR icfiar'ol L o w 9 BY 9 19 mm ATTORNEYSQL Feb. 21, 1950' Filed March 3, 1945 R. LOW

MOLD FOR SLIDE FASTENERS 7 Sheet-Sheet 3 FIG.

INVENTOR A 'clzarwl Law;

ATTORNEYS Feb. 21, 1950 I R. LOW 2,497,951

MOLD FOR SLIDE FASTENERS Filed March 3, 1945 7 Sheets-Sheet 4 iohar oz (2 12 ATTORNEYS.

Feb 21, 1950 R. LOW 2,497,951

MOLD FOR SLIDE FASTENERS Filed March 3, 1945 7 Sheets-Sheet 6 n4 A T I'LG we no \o4' loq. A: 981' me v2.3 no I04 122 c we.

94. in [02 as \\L. l0). I06 94 Feb. 21, 1950 R. LOW 2,497,951

MOLD FOR SLIDE FASTENERS v q glzagsli ll H G. 9 INVENTOR 507200 02 Zow ATTORNEYS Patented Feb. 21, 1956 UNITED; PATENT OFFICE 49% D O 4M A IE ER Richard Low, Ne vvarlg, ;N. 3., assignor to Compar Products fiorporation, Newark, N. J a corporatiQnof Ne w J ei s'e'y; ApplicationMarch 3, 1945, Serial No. 580,801

In a kn wn prior me ho ofmoldins o e or a up. of de. f stener lements fimore briefly. also. rererredtoher n sffscoops) d t to. a tape toproducemwhatis called, the slide fastener n er. the, tape. is fed; thr u h. a moldsmha a two-part mold, in the parting plane; .of the mold. and is p s ti n or seateddur a mo d: ing stepin theparting plane, The molding ma- I terial injected or die-cast into the mold isfed to, the slide fastener 7 element mold cavities,

(spaced along th be ed e e oi e tape) qm.

a sp channel t a dthmu h assaseways runners also located in the parting plane of the mold. In prior, molding methods of this type, only one tape is fed into the mold; and two tapes are themost that canpossibly be sofed. The reason for this limitationis that the tapes and the runners would intersect each other should more than two tapes be fed through the mold.

In prior apparatusfor molding slide fasteners accordingto this method, the passageways or runners for the molding material are thus locateclor arrangedas .is the tape in the parting plane of the two-part mold. Thewebofthe tape is positioned at one side of the scoop cavities and the runners are located at the, opposite side. for the molded structure formedin the runners and. sprue channel after solidification of. the molding material to be ejected together with the .formed appending scoops and the tape, It was customary to so construct these molds, having one plastic source (single nozzle machine), that only one tape is fed into the mold at a time. In such apparatus as used' heretofore two tapes, as stated, are-the most that can be fed to receive scoops at the same time; for in constructions of this latter possibility, the sprue channel and runners may be arranged between the two tapes, which in turn are or would be so fed and post,- tioned in the mold that they confront each other with their beaded edges.

The principal object of the presentinvention is the provision of a molding apparatus, in which more than twotapes may be simultaneously fed through. and, positioned in Y the parting plane of This arrangement thus makes it possible 2 the mold. and in which groups of slideufasteners or scoops maybe directly molded onto such tapes by molding material which is injected to and fed through runners also. located in the .parting plane of themold, all without the development of any intersecting interference between theta'pes and the runners.

Other and. ancillary objects pertain to the provision of. a molding apparatus of this'nature which is simply arranged and inexpensive to machine," and? a method whichmay bev practiced efficiently with mass production technique.

In accordancewithth'e principles of my present "invention; the tapes (a plurality, such' as three or more tapes) are fed and positioned during a molding cycle the parting; plane of a main two-part mold, and the molding material is fed to the tapes through a flow channel located in a'pian'e'dr the mmd'ain'erent' from the partmg plane thereof and thencet o thelrunners and scoopfcajvitiesiinf the plane l'of the mold, and

thereby the feeding of the molding material and I theieedingof the tapes are out ofintersecting and interfering relation. In carrying out this method'fthe said flow channel located out of the partingjplahe of the mold is covered by a mold member jprior to the molding step and is, uncovered" after the molding stepias when the. mold is opened, thus permitting the stripping from the mold jotthe tapejthe scoops molded theretolandfthematerial formed or molded in: the runnersand in said flow channel.

To thetrribdr'riplishment of the foregoing objects and suohother'o'bjects as may hereinafter appeQLI 'LIinYention relates to the process of molding slide. fastenerelements directly onto a tapefand thefmoldin'gfapparatus therefor sought to be def ned .injthel'app'ended claims and described in the following "specification, taken together" with the accompanying drawings in ii ch i I Fig. 1 is an elevational view of one part (the movablepart) .ofa two-part moldof my present invention, thisyiew showing the parting surface of the mold part;

Fig. 2 is a view takenin cross-section in the planes of the brolrien line .Z-f-Z ofFig. 1;

Fig. 3 is a view taken in cross-section in the planes of thebroken line 33 of Fig. 1, this view illustrating the rnold in closed position;

Fig. i is a viewlsimilar to Fig. 3 showing the lei opened P siti ns.

Fig.3 ,i's a side ele ational,view, with a part broken away, of the arrangement shownin Fig.

3 3 illustrating another step during the operation of this mold;

Fig. 6 is a plan view of a modified mold construction, this view taken in cross-section in the plane of the line 6-6 of Fig. 8;

Fig. 7 is an elevational view taken in crosssection in the plane of the line 1-1 of Fig. 6; this view showing the face of one of the mold parts;

Fig. 8 is a view taken in cross-section in the plane of the line 88 of Fig. 6, this view showing the face of the other mold part;

Figs. 9, 10 and 11 are views similar to Fig. 6 showing different positions of the mold parts of Figs. 6-8;

Fig. 12 is a plan view of another modification of a mold according to the present invention, this view being taken in cross-section in the plane of the line l'2--l2 of Fig. 14;

Fig. 13 is an elevational view taken in crosssection in the plane of the line l3|3 of Fig. 12;

Fig. 14 is an elevational view taken in crosssection in the plane of the line I 4-44 of Fig. 12;

Figs. 15 to 18 are views generally corresponding to Fig. 12 and are explanatory of difierent positions of the mold parts of Figs. 12 to 14; and

Fig. 19 is an elevational view of the movable mold part of still another modification of the mold of the present invention, this view also indicating the plastic fiow in both mold parts.

Before referring in detail to the drawings, reference may first be had, as broadly explanatory of the principles of the present invention, to some terms used hereinafter. While the terms sprue channel and runner indicate elements of any conventional injection mold, the terms subrunner and riser, as used herein, have been chosen to denote elements unique to the mold of the present invention. The term runner, for a mold of the class described, generally denotes a passageway for the molding material located in the parting plane of the mold and connecting the sprue channel and the mold cavity. subrunner, as used herein, denotes a passageway located in a plane different from the parting plane of the mold, the subrunner forming a part of the path of the plastic fiow between the nozzle or sprue channel and the mold cavities. The term riser, as used herein, denotes a connection between a subrunner and a runner.

For purposes of ready explanation, reference will now be made in a broad way to the four modifications of the molding method and apparatus depicted in the drawings.

Figs. 1 to illustrate a construction wherein in the closed position of the mold, the subrunners are covered by mold members arranged or located at the parting plane side of the subrunners. In this modification, these mold members are carried by the movable mold part. The subrunners are uncovered in the open position of the mold by the mold members so that the molded structure solidified in the runners, risers and subrunners and the sprue channel may be ejected. together with the molded scoops and tapes as a unitary piece. In this mold construction, theplastic or other material being molded first moves to the parting plane of the mold and thence to thesubrunners located in a plane of the mold different from (parallel to) the parting plane, and. thence by way of the risers back to the parting plane and on to the scoop cavities. With the mold of Figs. 1 to 5, only individual stringers can be molded. An individual stringer comprises a tape with a group of molded scoops.

Figs. 6 to 11 illustrate a construction wherein in the closed position of the mold, the subrunners are covered by a mold member arranged at a side of the subrunners remote from the parting plane of the mold. In this mold construction, the plastic first moves to the subrunners located, as before, in a plane of the mold different from (and also parallel to) the parting plane of the mold and thence by way of the risers to the parting plane, and finally to the scoop cavities. In this modification, the molded structure is ejected from the mold in two pieces instead of in a unitary piece. The molding of continuous stringers is possible with this modification of the invention. By continuous stringers is meant tapes with two or more groups of molded scoops thereon. With this mold, trimming of the stringers is performed outside of the mold.

Figs. 12 to 18 illustrate a mold construction which is similar to that of Figs. 6 to 11 in the respect that the mold member covering the subrunners is arranged at the side of the subrunners remote from the parting plane of the mold. The molding material or plastic on its path to the scoop cavities again first traverses the subrunners and then the runners. Here too, the molded structure is ejected or removed from the mold in two pieces instead of in a unitary piece. A preliminary trimming takes place inside the mold; hence continuous stringer lengths may be molded with this modification without any trimming operation outside the mold. A final finishing operation is carried out in any suitable way outside the mold.

In the mold shown in Fig. 19, the molding material again first moves to the subrunners, traverses the same and moves thence to the runners. Provision is here similarly made to cover and uncover the subrunners to eject or strip the molded product from the mold.

Referring now more in detail to the drawings, and referring first to Figs. 1 to 5 thereof, the molding apparatus comprises a main two-part mold consisting of the relatively stationary mold part A and the relatively movable mold part B meeting in the parting plane P. The mold part-s A and B are provided with tape seats which mate in the parting plane of the mold and with scoop cavities, which also mate in the parting plane of the mold. The mold part A is thus provided or formed with a plurality of tape seats s, s, and the mold part B is provided with the mating tape seats 8', 8' (see particularly Fig. 2), which seats mate in the parting plane of the mold to form the composite seats S, S for seating the beaded tapes T, T. The tape seats are machined in the faces of the mold parts A and B to define the composite seats S, S; and each seat, therefore, is made to comprise a groove 20 and a side terminal channel 22 (see particularly Fig. 1) having a depth equal to one-half the thickness of the tape and the tape bead respectively. The mold part A is also formed with a plurality of scoop cavities c, 0 arranged in groups, a group being associated with a tape seat; and these scoop cavities of the group are spacedly arranged along the channel 22 of such seat. The mold part B is similarly provided with the scoop cavities c, 0' arranged in corresponding groups, a group associated with each tape seat s and the elements of each such group are also spacedly arranged along the length of a channel 22 of such seat as best depicted in Fig. 1 of the drawings. The groups of cavities c in the mold part A mate with the corresponding group of cavities c in the mold part B to 'form the composite or completed scoop cavities C (see Fig. 2),.the mating being in'the parting planeof the mold.

In the mold shown in Figs. 1 to 5, provision is made for the molding of four complete stringers each having eleven scoops, which scoops are molded at one time or in one shot. The four tapes T, T are simultaneously fed into the mold and inthe parting plane thereof. Thererare thus provided in the mold parts A and B tape seats defining four composite seats S, and groupsof scoop cavities forming or defining four composite or completed groups of slide fastener element cavities C.

For leading the molding material from a common nozzle to all of the groups of scoop cavities, the mold parts A and B are formed with flow channels or passageways. Lying in the parting plane of the mold and formed in at least one of the mold parts, here the movable mold part B, are the main runners or passageways connected and leading to the scoop cavities C, C, these comprising in the embodiment shown in Figs. 1 to 5, the two runners R, R,.iormed in the parting face of the mold part B provided with branch channels leading to the scoop cavities C, C. In the mold of Figs. 1 to 5, the moldedmaterial is injected through anozzle (not shown) into a sprue channel 24 formed in the stationary mold part A from whence the plastic material flows centrally in oppositely-directed branches into a main passageway 215, also formedin the parting lace of the movable mold part B.

To carry out the principles of the present .invention, the plastic material from the sprue channel 2 2 and the passageway 26 is led or caused to flow to the runners R, R in such a way as to avoid interferingintersection with the positioning or the movement of the tapes I, T in the parting plane of the mold. This is accomplished by providing subrunners R, R (see particularly Fig. 2) located in a plane of the mold different from the parting plane thereof, and in the embodiment shown in the drawings these subrunners are located in one of the mold parts in a plane preferably parallel to the parting plane of the mold, and these subrunners R, R communicate with the runners R, R, by means of the risers 1', r (see Fig. 2). The subrunners connect to the main passageway 26 by means of the ducts 28-28.

By means of this construction and arrangement, it will be seen that the molding material may be fed from a common or single source, such as a nozzle, to the-scoop cavities of a group of tapes (three or more) which are fed in the parting plane of the mold without any interfering intersection taking place between the feeding of the tapes (or the tapes) and the fiow of the plastic material. This. relationship and result are particularly evident from viewing Figs. 1 and 2 of the drawings.

To enable all of the molded material to be ejected from the mold, means are provided for covering the subrunners R, R prior to the molding step as when the mold is closed and for uncovering the subrunners after a molding step'as when the mold is opened. In the mold shown in Figs. 1-5, such means is made to comprise a mold member, or members, located or arranged on the parting plane side of the subrunners so that when the subrunners are uncoveredwith the opening of the mold, there may be ejected or stripped from the moldin one unitary piece,'.the tape, the molded scoops and the material molded 6 in the runners, risers and subrunners. These mold members comprise the membersm, m shown in Figs. 1 and 2 as covering the subrunners R, R, four of these membersm being used in this form of the invention tocover (and uncover) the four subrunners R, R.

For covering and uncovering the subrunners, the members .m', m are connected to each other and are preferably formed integrally with slide members 3ll3fl mountedforslidable movement in themovable part B. Two of such slide members 30-30 are employed in the mold of Figs. 1 to 5, relatively 'slidable in the mold part3 in'opposite directions. When themold is closed, these slide members 30-30 assume the positions shown in .Figs. 1 and 2 for covering the subrunners and when the mold is opened, these slide members assume the position shown in .Fig. 4 of theudrawings for uncovering the subrunners. For keying the slide members to the mold part B, they are provided with the end dovetails 32-32, and themoldpart B is suitably grooved, as shown, :to receive these slide members. It is preferred .tomove these slide members in the process of opening and closing of the mold so that they are moved to uncoverthe subrunners during the opening of the mold, and to cover the subrunners during the closing of the mold. This .may simply be accomplished by providing a plurality of relatively stationary cam bars 34--34 the camming ends 36 of which are received by and accordingly mate with camming openings 3838, which may be formed in theopposite sides of the slide members. 3l30. The construction and arrangement is such, as shown in Figs. 1,v 3, and 4 that, as the movable part B is movedfrom the closed position, shown in Fig. .3, to the open position, shown in Fig. 4, the slide members 3030 are moved simultaneously away from the horizontal medial plane of the mold so as to uncover the subrunners and so that when the movable mold part .B is returned to closed position, these slide members 3Il-3U assisted byithe restoring springs dill-4w housed in the mold part B are returned or .moved backto the positions shown in Figs. 1 to 3 of the drawings for covering or re-covering the subrunners.

The flow of the plastic material, when the mold is closed, is from the sprue channel 24 to the passageway 26, thence through the connecting ducts 28, thence through the subrunners R, thence to the risers r, and finally to the runners R leading into the scoop cavities C. The molding material when injected into the mold and when solidified thus forms not only the scoops, but also a structure connected to the scoops and formedin the runners, subrunners and risers, as well as the other appending parts including the sprue. Thus, as best depicted in Fig. 5 of the drawings, the molded structure which is to be removedfrom the mold after a molding operation comprises the tape T, the scoops 42 molded thereon,.the strips formed in the runners, connecting pieces 46 formed in the ducts and'risers, the strips 48 formed in the subrunners, and other appending parts including the strips formed in the passageway 26, and the sprue 50 formedin the sprue channel. This described molded structure not only inter-connects all of the molded scoops, but also unites the group of tapes (four in number) T, T. The tapes, together with the scoops and all of this appending molded structure form a unitary piece.

:By the movement of the mold members m, m to the uncovering position, this unitary .piece may be ejected and stripped from the mold of Figs. 1 to in a single operation and in one piece. When the movable part B is moved from the closed position of Fig. 3 to the open position of Fig. 4, the slide members 3ll30 are, as described, moved in opposite directions away from the horizontal medial plane of the mold, resulting in the uncovering by the mold members m, m of the subrunners R, R. The unitary piece referred to is, therefore, in a condition to be stripped as a unit from the movable mold part B. As the movable mold part B moves from the mold part A, a sprue puller 52 located centrally of the mold part B, which in the molding operation attaches itself by its hooked end 54 to the sprue 50 pulls the described unitary piece out of the stationary mold part A so that this unitary piece remains lodged in the movable mold part B. When the parts assume the position shown in Fig. 4 with the subrunners uncovered, knockout or ejecting rods 56-56 come into play by engagement with a stationary plate 58 (see Fig. 5) to push or eject the unitary piece referred to out of the movable mold part, as shown in Fig. 5 of the drawings. This ejecting operation at the same time frees this unitary piece from the sprue puller 52. After this unitary piece is thus freed from the mold, the tapes T, T and the appending molded structure are moved in the feeding direction of the tapes and the molded scoops are thereafter trimmed.

Thus the design of the mold of Figs. 1 to 5 is such that the unitary piece referred to may be ejected from the mold as a single unit. This mold is suitable for the making of individual stringers as distinguished from the continuous stringer lengths. All of the molded material is thus removed from the mold in the stripping operation and when a new group of tapes is fed into the tape seats in the mold, the mold part B is returned to closed position ready for a new or fresh molding cycle.

In the modification of the invention shown in Figs. 6 to 11, the two main mold parts are the parts A and B, and these have the parting plane P. For convenience and clarity, the tape seats and the molding passages, as well as the molded parts, are designated in these views by the same reference characters used in Figs. 1 to 5. Thus the tape seats are S, S; the tapes T, T; the scoop cavities C, C; the runners R, R; the subrunners R, R; the risers 1', r; and the molded unit comprises the tapes T, T, the scoops 42, the runner strips 45, the subrunner strips 48, the connecting pieces 46 and the sprue 50. Also in the mold part A, there are the tape seat halves s, s, and the scoop cavity halves c, 0; while in the mold part B, there are the mating tape seat halves s, s, and the mating scoop cavity halves c, 0 (see Figs. '7 and 8). It will be noted that the runners R, R and the ducts connecting them to the scoop cavities C, C, need only be formed in one mold part and are accordingly formed only in the mold part B (see particularly Fig. 8).

In this modification of Figs. 6 to 11, the mold members for covering and uncovering the subrunners is located on the side of the subrunner remote from the parting plane P. This mold member may conveniently consist of a stationary receptacle block 60, recessed as at 62 for receiving the mold part A. The mold part A may broadly be considered as consisting of the mold section A, and the receptacle block or mold member 60. These elements of the mold part A are relatively movable for covering and uncovering the subrunners R, R. The subrunners proper ma be formed either in the mold section A or in the mold member 60, the latter being indicated in the drawings.

For opening and closing this mold and for covering and uncovering the subrunners, the following mechanism is provided: two rods 64 slidably received in the mold part B are press fitted at B6 to the mold section A. A tube 68 likewise slidably arranged in the mold part B is press fitted at 10 into a plate 12 housed in a recess 14 in the underneath wall of the mold section A. This tube 68 is provided with the bottom hooks l6. slidably mounted in the tube 58 is a knockout rod 78; and slidably mounted in the mold part B are the knockout pins 80, 80.

With the mold ready for molding, the charge of the molding material is flowed through the sprue channel 24, the subrunner R, the risers r, and the runners R to the scoop cavities C. The units that are molded comprise the scoops 42 molded to the tapes T, and the appendage structures consisting of the runner strips 44, the subrunner strip 48, the connecting pieces 45 and the sprue 58. In the form of the invention of these Figures 6 to 11, this unitary piece is broken into two parts for stripping from the mold in a manner now to be described.

The operation of this modification can best be seen in Figs. 9 to 11. After solidification of the fluent mass, the mold is opened. The mold parts A and B are first moved together and away from the mold member 80 in the direction indicated by the arrow X in Fig. 9. Thereby the molded unitary piece is pulled away from the mold member 50, the subrunner R being uncovered, as clearly shown in Fig. 9. This pulling away of the molded unit is assisted by the hooks 76 of the tube 68 which embed themselves in the subrunner strip 48 and act as a sprue puller.

The next two operational stages are depicted in Fig. 10. In the first stage, the plate '12 is forced by the tube 68 (and ejecting rod l8) out of the recess 14 in the direction indicated by the arrow to the position shown in full lines in Fig. 10. It will be noted that the risers r and consequently the molded parts 46 are tapered in opposite directions so that their cross-sections are smallest at about their mid-points. Consequently, this described movement causes the molded parts 48 to break at their weakest points, thereby causing the sprue 56, the subrunner strip 48 and parts of the riser pieces 46 to break away from the other molded parts (Fig. 10). The second stage consists of separating the broken away molded parts from the plate 12. This is accomplished by the knockout rod 18 which is now moved in the tube 68 to force the broken away molded parts away from the plate E2 to the detached dot-and-dash line position shown in Fig. 10, thus stripping this part of the molded structure away from the mold.

The last operational step is shown in Fig. 11. The mold part A is moved away from the mold part B by the rods 64 in the direction of the arrow Z to free the structures each consisting of two tapes T, the scoops 42 molded thereto, the runner strip 44 and a part of the riser piece 46. The mold part B is provided with recesses 82 which are slightly tapered (Fig. 11) so as to permit the mold part A to be moved away free from this remaining molded structure, leaving the latter lodged on the mold part B. The

movement of 'themold art A is carried out to a point where the *plate "I2 'is againr'eceived by the recess "I4 in the mold-partl fThis remaining molded structure is then ejected from the mold part B by means of the knockout pins 80.

This mold may be used for molding continuousstringer lengths. Atrimming operation must be performed, however, outside the mold between molding cycles. In the mold shown, five scoops are molded onto each of the four tapes at a time. Any other suitable number of scoops may be molded in a single shot.

In the modification shown in Figs. 12 to 18, the two main mold parts are the parts A? and B and'these have the parting plane P for convenience and clarity, the tape seats and the molding passages, as well as the molded parts, are designated in these views by the same reference characters used in the preceding views.

Thus the tape seats are .5, S the tapes are T, T;

the scoop cavities are C, C; the runners are R, R; subrunners are R, R"; the risers are r, r; and the molded unit comprises the tapes T, T, the scoops 42, the runner strips 44, the subrunner strips 48, the connecting pieces 46 and the sprue 50. Also in the moldpart A there are the tape seat halves 8, s, and the scoop cavity halves c, 0; while in the mold part B there are the mating tape seat halves s, s", and the mating scoop cavity halves c',c' (see Figs. 13 and 14). J

It will be here also noted that the runners R, R and the ducts connecting them to the scoop cavities C, C, need only be formed in one of the mold parts and these are accordingly formed only in the mold part B (see particularly Fig. 14).

In this modification of Figs. 12 to "18, the mold member for covering and uncovering the subrunners is located (as in Figs. 6 to 11) on theside of the subrunner remote from the parting plane P This mold member may here also conveniently consist of a stationary receptacle block 90, recessed as at 02 for receiving the mold part A The mold part A may here too broadly be considered as consisting of a mold section A which mates with the mold part B and the receptacle block or mold member 90. These parts of the mold part A are relatively Inovable for covering and uncovering the subrunners R, R. The subrunners proper may be formed either in the mold section A or in the mold member 90, the latter being indicated in the drawings. I

For opening and closing this mold, for covering and uncovering the subrunners andfor also producing a preliminary trimming of the produced stringers, the following mechanism is provided: two rods 04 slidably received in the mold part B are press fitted at 96 to the mold part A A sprue puller 98 likewise slidably arranged in the mold part B is press fitted at I00 to the mold part A and has its bottom hooked end projecting therethrough for anchoring to the subrunner strip 48. Two punches I02, sl i-dably mounted in the mold part B are located in registry with the risers 1' and are adapted to punch circular holes in the runner strips 44 (see Figs. 12, i4 and 16). Knockout rods IM also slidably movable in the mold part B are located to engage the runner strips 44.

With the mold ready for molding, the charge of the molding material is flowed, as before, through the sprue channel 24, the subrunners R, the risers r, and the runners Rto the scoop cavities C. The units that are molded comprise the scoops H-molded to-thetapes T, and the append Again Figs. 12 to 18 are illustrated sequentially in Figs.

After solidification of the fluent mass, the mold is opened. The mold parts A and B are first moved together and away from the mold member 00 in the direction indicated by the arrow X in Fig. 15. Thereby the molded unitary piece above described is pulled away from the mold member 00, the subrunner B being thereby uncovered, as clearly shown in Fig. 15. This pulling away of the molded unit is assured by the sprue puller 98.

The next two operational stages are depicted in Fig. 16. In the first stage, the punches I02 are moved in the direction of mold part A resulting in the punching of circular holes centrally in the runner strips 44 and thereby shearing off the molded parts consisting of the sprue 50, the subrunner strip 48 and the two riser pieces 46, leaving in the mold only the runner strips 44 connected to the stringers. In the second stage, the punches I02 are caused to descend further and thereby eject the sheared ofi molded parts from the mold part B? as indicated by the dot-anddash showing of Fig. 16. The punches I02 thereby also function as knockout pins.

The next operational stage is depicted in Fig. 1'7 and comprises the separating or opening of the mold parts A and B by moving the mold part A by means of the rods 94 in the direction depicted by the arrow Z to the position shown in this figure. The two molded sheared structures each consisting of two tapes T, the scoops 42 molded thereto, and the runner strips M are thus freed for stripping. The mold part B is provided with recesses I 04 which are slightly tapered (Fig. 17) so as to permit the mold part A t to be moved away free from this sheared molded structure, leaving the latter lodged on the mold part B These structures are now ready to be stripped from the mold.

In this form of the mold, the mold part B may be made in two sections, namely, a main section I06 (see particularly Fig. 14) and a receptacle block section I08, the section I 06 being formed with two rectangular apertures I I0 which mating ly receive the boss portions H2 of the receptacle section I 08, these sections being arranged in telescoping relation, "as best shown in Fig. 18. Press fitted into the section I [it are the four rods 4. By means of this arrangement, the final operational stage is facilitated, as particularly shown in Fig. 18. The knockout pins I04 act upon the runner strips M while the mold section I 06 is moved in the same direction as the knockout pins by means of the fourrods H4, which rods slide in the section 508 of the mold part B The section I05 helps to separate the sheared off molded parts in the mold since the tapes T are held under tension, and the section I05 supports the tapes during feeding, the tapes being guided by those portions of the tape seats formed in the section I66. The molded structures are thereby stripped more readily from the mold part B The mold of these Figs. 12 to 18 has the advantage that a preliminary trimming takes place in the mold, and that continuous stringer lengths 3'5 may be molded-without any intermediate trimming operation outside the mold. After shearing off and ejecting the molded parts as shown in Fig. 16, there remain the stringers and appending runner strips in the mold which are suitable for being enclosed in the mold during the next immediate molding cycle. This may be seen by following out the feeding step which is as follows: As soon as the mold has been opened, each of the four tapes T having seven scoops molded thereon in one shot is fed (see Fig. 14) such a distance that the scoop indicated by I2?! comes to a position in line with mating cavities I22 in the mold part B and I24 in the mold part A (Figs. 13 and 14); I22 and I24 designate four pairs of complementary cavities in the mold parts A and B which form pilot cavities to receive the first scoops of the rows molded in the last shot. The tapes are fed while supported by the mold section I06, as shown in Fig. 18. Slots I26 and I28 (Fig. 14) receive all of the other scoops and the runners of a previous shot, which scoops and runners are enclosed by the mold during the following molding cycle. The mold is now closed and is ready for the next shot.

The method and mold as contemplated by the present invention may be used to manufacture any type of scoop. The molds shown in Figs. 1 to 18 have been designed for scoops which can be molded without the use of cores. In Fig. 19 a mold is shown to illustrate that this invention may be applied as well to scoops of conventional shape, i. e., scoops having a projection on one face and a pocket in the opposite face. Such conventionally shaped scoops are molded with the use of cores. The mold of Fig. 19 makes use of the disclosure of the co-pending application of Joseph-N. Kuzmick, Serial No. 533,989, filed May 3, 1944, now Patent No. 2,439,433, entitled Manufacture of slide fasteners.

Referring now in detail to Fig. 19, the molding material is supplied through a sprue I30 to subrunners I32, I34, the sprue and subrunners being shown in phantom. The subrunners extend within the stationary mold part (not shown) in a plane parallel to the parting plane of the mold and are covered by a member similar to those of the arrangements shown in Figs. 6 to 18. From the subrunners of the mold the molding material moves through risers I36 and I38 (still within the stationary mold part) and a system of runners in the parting plane to the scoop cavities. The plastic, after solidification in the runners, forms a structure comprising longitudinal arms I40, I42, and short branches I44. The cores I46 form the scoop pockets. It will be understood that the molding material according to this mold construction, is supplied separately to each of the four tapes shown in Fig. 19. This arrangement enables the stringers formed to be stripped off the cores after the risers and subrunners have been punched off and ejected. This punching off and ejecting operation can be carried out as explained in connection with Figs. 12 to 18. The stringers are stripped off in the direction indicated by the arrows W.

While I have shown and described the method and apparatus of my present invention in a number of preferred forms, it will be obvious that many changes may be made in the sequence and character of the steps and in the parts of the mold apparatus without departing from the spirit of the invention defined in the following claims.

I claim:

1. A molding apparatus for molding slide fastener elements directly onto a tape, comprising a main two-part mold provided with mating tape seats and slide fastener element cavities mating in the parting plane of the mold, the tape seats being adapted to receive tapes fed in the parting plane of the mold, said mold being provided with runners leading to said cavities and lying in the parting plane of the mold, the said mold having a subrunner located in a plane of the mold different from the parting plane thereof and a riser connecting the subrunner to the runner, the molding material being adapted to be flowed into the subrunner, thence to the riser, the runners and the element cavities, the said mold including a mold member in one of said mold parts covering said subrunner during a molding step, whereby the flowing of the molding material and the feeding of the tapesare out of intersecting relation, the said mold member being arranged to uncover the subrunner after the molding step for stripping from the mold the tape, the molded fastener elements and the material molded in the runners, the riser and the subrunner.

2. A molding apparatus for molding slide fastener elements directely onto a tape, comprising a main two-part mold provided with mating tape seats and slide fastener element cavities mating in the parting plane of the mold, the tape seats being adapted to receive tapes fed in the parting plane of the mold, said mold being provided with runners leading to said cavities and lying in the parting plane of the mold, one of said mold parts having a subrunner located in a plane of the mold different from the parting plane thereof and a riser connecting the subrunner to the runner, the molding material being adapted to be flowed into the subrunner, thence to the riser, the runners and the element cavities, the said mold including a mold member in said one of said mold parts covering said subrunner during a molding step and arranged at the parting plane side of the subrunner, whereby the flowing of the molding material and the feeding of the tapes are out of intersecting relation, the said mold member being movable to uncover the subrunner after the molding step for stripping from the mold in one piece the tape, the molded fastener elements and the material molded in the runners, the riser and the subrunner.

3. The molding apparatus of claim 2 in which the said mold member is mounted in its said mold part for slidable movement therein for covering and uncovering the said subrunner.

4. In the molding-apparatus of claim 2, means for moving the mold member, operating responsive to the opening and closing operations of the mold, to cover the subrunner when the mold is being closed and to uncover the subrunner when the mold is being opened.

5. The molding apparatus of claim 2 in which the said mold member is mounted in its mold part for slidable movement therein for covering and uncovering the said subrunner, combined with means responsive to the opening and closing of the mold for sliding said mold member, said means operating to cover the subrunner when the mold is being closed and to uncover the subrunner when the mold is being opened.

6. A molding apparatus for molding slide fastener elements directly onto a tape, comprising a main two-part mold provided with mating tape seats and slide fastener element cavities mating in the parting plane of the mold, the tape seats being adaptedto receive tapes fed in the parting plane of the mold, said mold being provided with runners leading to said cavities and lying in the parting plane of the mold, one of said mold parts having a subrunner located in a plane of the mold different from the parting plane thereof and a riser connecting the subrunner to the runner, the molding material being adapted to be flowed into the subrunner, thence to the riser, the runners and the element cavities, the said mold part including a mold member covering said subrunner during a molding step and arranged at the side of the subrunner remote from the parting plane of the mold, whereby the flowing of the molding material and the feeding of the tapes are out of intersecting relation, the said mold member being arranged to uncover the subrunner after the molding step for Stripping from the mold the tape, the molded fastener elements and the material molded in the runners, the riser and the subrunner.

7. A molding apparatus for molding slide fastener elements directly onto a tape, comprising a main two-part mold provided with mating tape seats and slide fastener element cavities mating in the parting plane of the mold, the tape seats being adapted to receive tapes fed in the parting plane of the mold, said mold being provided With runners leading to said cavities and lying in the parting plane of the mold, one of said mold parts having a subrunner located in a plane of the mold different from the parting plane thereof and a riser connecting the subrunner to the runner, the molding material being adapted to be flowed into the subrunner, thence to the riser, the runners and the element cavities, the said subrunner containing mold part comprising a mating mold section and a mold member covering said subrunner during a molding step, said mold member being arranged at the side of the subrunner remote from the parting plane of the mold, whereby the flowing of the molding material and the feeding of the tapes are out of intersecting relation, the said mold member and mating mold section being relatively movable to uncover the subrunner after the molding step for stripping from the mold the tape, the molded fastener elements and the material molded in the runners, the riser and the subrunner.

8. In the molding apparatus of claim 7, means for relatively moving the said mating mold section and mold member to uncover the subrunner, means for stripping from the mold the material formed in the subrunner, and means for stripping from the opened mold the tapes, the molded fastener elements and the material molded in the runners and risers.

9. In the molding apparatus of claim 7, means for separating the said mating mold section and mold member to uncover the subrunner, means for stripping from the mold the material formed in the subrunner and in part of the riser, and means for stripping from the opened mold the tapes, the molded slide fastener elements and the material molded in the runners and in part of the riser.

10. In the molding apparatus of claim '7, means for separating the said mating mold section and mold member to uncover the subrunner, means for stripping from the mold the material formed in the subrunner and in its riser, and means for stripping from the opened mold the tapes, the molded slide fastener elements and the material molded in the runners.

11. A molding apparatus for molding slide fastener elements directly onto three or more tapes comprising a main two-part mold provided with mating tape seats and slide fastener element cavities mating in the parting plane of the mold, the tape seats being adapted to receive the tapes fed in spaced relation in the parting plane of the mold, said mold being provided with a single nozzle, a sprue channel, runners leading to said cavities and lying in the parting plane of the mold, a subrunner located in a plane of the mold different from the parting plane thereof connected to said sprue channel and a riser connecting the subrunner to the runners, the molding material being adapted to be flowed from the sprue channel into the subrunner, thence to the riser, the runners and the element cavities, the said mold including a mold member in one of said mold parts covering said subrunner during a molding step whereby the flowing of the molding material and the feeding of the tapes are out of intersecting relation, the said mold member being arranged to uncover the subrunner after the molding step for stripping from the mold the tape, the molded fastener elements and the material molded in the runners, the riser and the subrunner.

12. The molding apparatus of claim 11 in which the said mold member is mounted in its said mold part for slidable movement therein for covering and uncovering the said subrunner.

13. In the molding apparatus of claim 11, means for moving the mold member, operating responsive to the opening and closing operations of the mold, to cover the subrunner when the mold is being closed and to uncover the subrunner when the mold is being opened.

14. The molding apparatus of claim 11 in which the said mold member is mounted in its mold part for slidable movement therein for covering and uncovering the said subrunner, combined with means responsive to the opening and closing of the mold for sliding said mold member, said means operating to cover the subrunner when the mold is being closed and to uncover the subrunner when the mold is being opened.

RICHARD LOW.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,043,584 I-Iusted June 9, 1936 2,163,814 Swarovski I June 27, 1939 2,302,342 Nast Nov. 17, 1942 2,374,292 Kuna Apr. 24, 1945 FOREIGN PATENTS Number Country Date 361,092 Great Britain Nov. 19, 1931 OTHER REFERENCES Ser. No. 285,944, Swarovski (A. P. C.) pub. Apr. 2'7, 1943. 

